The present invention relates to a process for the preparation of substituted phosphonium salts such as tetrakis(hydroxymethyl)phosphonium chloride. More particularly the present invention is directed to a new method for the preparation of such compounds which avoids the difficulties of prior art processes such as the necessity for employing highly toxic and difficult to handle reactants, such as phosphine, as starting materials.
Other prior art processes for the production of phosphonium salts have employed phosphine, PH.sub.3, as the starting material, but this compound is dangerous and difficult to work with. Phosphine is a gas which ignites spontaneously when mixed with air, so that rigid safety precautions are necessary in employing phosphine in an industrial organic preparation.